Action
Final rule.
Summary
The FAA is superseding Airworthiness Directive (AD) 2016-17- 12, which applied to all Airbus SAS Model A318 series airplanes; Model A319-111, -112, -113, -114, -115, -131, -132, and -133 airplanes; Model A320-211, -212, -214, -231, -232, and -233 airplanes; and Model A321- 111, -112, -131, -211, -212, -213, -231, and -232 airplanes. AD 2016- 17-12 required inspecting certain trimmable horizontal stabilizer actuators (THSAs) to determine the number of total flight cycles the THSA has accumulated, and replacing the THSA if necessary. Since the FAA issued AD 2016-17-12, the FAA has determined that a more restrictive airworthiness limitations is necessary for carbon friction disks on the no-back brake (NBB) of the THSA. This AD continues to require the inspections of the THSAs and replacement if necessary. This AD also requires revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations; as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. This AD also limits the installation of affected parts under certain conditions. The FAA is issuing this AD to address the unsafe condition on these products.